A clutch release mechanism for a push-type friction clutch used in motor vehicles is disclosed in DE 199 12 431 A1. The mechanism includes a release bearing, which is mounted on a sliding sleeve, and a disk spring, which is part of the friction clutch and is in working connection with the release bearing. Particularly, the disclosed mechanism includes two areas with complementary surfaces in the form of segments of a sphere that are provided between the disk spring and the release bearing. The two areas with the spherical segments are provided directly or indirectly on the disk spring; and the areas forming the spherical segments can be shifted radially toward the release bearing.
The areas of the spherical segments are slideable with respect to each other. The slideable surfaces, i.e. areas, are formed from a finger of the disk spring, i.e. release spring, and a flange-like contact surface of a compensating ring of the release bearing.
The complementary spherical segments are subjected to continuous wear as they swivel against each other at a high frequency due to inherent vehicle vibrations. When the elements with the complementary spherical segments must compensate for a tilt of the center axis of the friction clutch with respect to the center axis of the guide sleeve and/or for a wobbling eccentricity or gyration of the release spring, they are in constant contact with each other as they move. Disadvantageously, as the friction clutch becomes worn, abraded material also accumulates, especially in the area of the release mechanism. This material cannot be kept away from the surfaces which slide across each other. Furthermore, it is very expensive to produce two elements with perfectly matching spherical surfaces.